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<H1>help(+PredSpec)</H1>
Prints help information on the specified predicate in PredSpec on the
current output.


<DL>
<DT><EM>PredSpec</EM></DT>
<DD>Predicate/Library specification in form Name/Arity or Module:Name/Arity, lib(Name), or an atom Name
</DD>
</DL>
<H2>Description</H2>
   Prints help information about the specified predicates to the current
   output.  The information displayed is a text version of the reference
   manual.  If only Name is specified, the system looks for all predicates
   that have this atom in their name.  If there are more than one predicate
   matching, a short description for each one is printed, rather than the
   whole page.  For instance, help var prints the short description of
   get_var_info/3, nonvar/1, readvar/3, var/1 and variant/2, whereas help
   dv prints the whole reference manual page for readvar/3.

<P>
   Help information is available for both built-ins (those predicates
   defined in eclipse_language) and library predicates. If a particular
   predicate is available in more than one library, the user can specify
   Module:Name/Arity for PredSpec where Module is the name of the library 
   to select a specific predicate description. If a predicate is available
   both as a built-in and library predicate(s), then the built-in will be
   printed in full, while short descriptions are given for the library
   predicates.
<P>
   In addition, if information on library is available, help
   lib(LibraryName) can be used to obtain this information.


<H3>Modes and Determinism</H3><UL>
<LI>help(+) is semidet
</UL>
<H3>Fail Conditions</H3>
Fails if no help is available for PredSpec
<H2>Examples</H2>
<PRE>
Success:
      help(nl/0).         % Displays reference page on nl/0

      help(write/X).      % Displays short description of
  % write/1 and write/2

      help(fd:(::)/2).    % Displays the reference page for fd's ::/2.

      help((=:=)/2).      % Displays reference page for the built-in =:=/2,
  % and short description of the other instances of =:=/2.

      help(lib(eplex)).   % Displays the reference page for the library eplex.
      help(X).            % Displays short description of
  % all built-ins

Fail:
      help(nobip/1).




</PRE>
<H2>See Also</H2>
<A HREF="../../kernel/compiler/current_built_in-1.html">current_built_in / 1</A>
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